There are a wide variety of domestic food mixers, which are currently being marketed and which may be categorized into two broad classifications. The first classification includes the well-known lightweight mixer of the portable variety often used for mixing small amounts of material. The other type of mixer is the stand type, which is used for mixing larger quantities and has recently been used for kneading bread doughs and mixing other heavy foodstuffs as well.
The stand mixer may be described as having a drive unit within a housing mounted on a stand having a turntable. The turntable is rotatably mounted on a central rotating assembly having a shaft and center bearing and receives a bowl for holding the material to be mixed. The periphery of the turntable is unsupported. The prior art mixer housing can pivot from the beater up position to the beater down position. In the past, the weight of the housing unit over the beaters has been sufficient to provide adequate stability to the food mixer during operation.
In these prior art stand mixers, the use of medium power electric motors, for instance in the range of 230 to 240 watts, has been sufficient for most domestic uses. It is well-known that commercial mixers and certain orbiting head stationary bowl mixers are driven by somewhat higher powered electric motors.
The interest of many users of kitchen appliances in making their meals from basic ingredients has resulted in a demand for home food mixers of the rotating turntable variety, which can efficiently mix many foods and knead doughs. The kneading of dough is one of the most difficult tasks which a domestic mixer performs. The necessity of using dough hooks rather than whippers is apparent. However, problems have occurred in the past with commercially available dough hooks in that the dough hooks were sometimes driven so that the mixer head was pulled toward the bowl, thereby causing the dough to climb the dough hooks. If the dough hooks were operated in the reverse direction to prevent dough from rising upwardly along the dough hooks, the mixer head, in consequence, would be forced up and out of the dough, thereby causing the mixer to knead a relatively small portion of the dough. Furthermore, the heavy loads placed upon the conventional mixer could not be met by the medium power motors then available. The center support for the turntable also adds to the instability of the unit, since the off-center loading of the turntable during dough kneading operations is high, thereby introducing mechanical play into the machine.
Accordingly, it would be desirable to have a heavy duty food mixer with a rotating turntable, which can better perform tasks such as dough kneading than prior art food mixers.